Question $2.$ On a day that there is no wind you drive over the bridge just down stream of the discharge, and you stop and get out of your car to go down and look at the river. If you are $2$ meters above the surface of the river and the bridge has a sensor that measures Styrene concentration at $10$ meters. The measured concentration of Styrene is $1$ ppb $($vol$/$vol$).$ Can you smell the Styrene? What is the flux rate of Styrene coming out of the river through volatilization? The threshold for odor of Styrene is $0\mathrm{.}32$ ppm $($vol$/$vol$)$

C at surface of water $=31\mathrm{.}25$ g$/$L

Diffusivity of Styrene in air $=0\mathrm{.}252$ cm$^2/$s